This invention relates to sealing devices and more particularly to multi-component sealing assemblies useful with a bearing shaft and housing system where a liquid differential pressure is present.
In most industries, it is extremely important that there be provided a seal which prevents the fluids associated with pumping, mixing or lubrication of bearings from leaking externally of an associated housing or bearing support and for preventing foreign particles in the pumped fluid or environment from working themselves through the seal and/or into the bearings.
In fact, the need of an effective sealing means may be more critical than in the more common ball bearing shaft and housing systems as disclosed in U.S. Pat. No. 4,114,902.
In the above-cited patent, there is a two-ring sealing structure disclosed where the mating flange of one ring has at least one groove with respect to the recess (in which the flange fits) on the other ring. A groove is also provided on the inwardly facing wall of the recess. The grooves act to inhibit foreign particle migration axially along the shaft.
The present invention provides a more effective seal in that the sealing structure of the prior art is not effective in all cases such as when the sealing structure is submerged under the liquid lubricant level or where a differential fluid pressure exists, as is the case with rotating pumping or mixing equipment. In such an arrangement, where the sealing assembly is below the level of the lubricant, there is a pressure differential, i.e., from a higher to a lower pressure, and the prior art seals are not adapted to seal off lubricants, fluids or contaminants in such a system as is the present improved seal.
The present seal, which is a "radial" seal, is not subject to a multitude of variables which tend to destroy the conventional "axial end-face" mechanical seals. The present seal being essentially a pressure differential seal and is adapted to seal the leakage of lubricating fluid from the bearings and the passage of pumped fluids into or from the sealed or inner areas. In such instances the use of the present sealing assembly has been found to be quite effective.